Security add-on for Firefox. WOT, Web of Trust, warns you about risky websites that try to scam visitors, deliver malware or send spam. Protect your computer against online threats by using WOT as your front-line layer of protection when browsing or searching in unfamiliar territory. WOT’s colour-coded icons show you ratings for 21 million websites – green to go, yellow for caution and red to stop – helping you avoid the dangerous sites.